Bomb



Patentecl Jan. 4, 1949 vI TED S TATES OFF] CE I 2,451,817 30MB Garland ii. HarrelL'Hurst, I Application Marcl131, 19 i4, Serial No. 528,999

(Granted under the act :of 'March i3, vMitt-3,26

amended April 30,, 1928; 374) 0. G. 757

"5 Claims.

The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

The invention relates to multiple unit :antipersonnel, demolition, and fragmentation bombs and projectiles, and mines, and "hasfor an'aimportant object to enable the conversion of conventional high explosive projectiles or bombs not ordinarily dependent for utility on fragmentation, into combined hig'h concussion detonating and multiple unit fragmentation ammunition; and also alternatively to enable the conversion of the ordinary single container fragmentation bomb or projectile into a dispersib'le multiple container instrument in which an initial demolition or fragmentation explosion of'high'ly destructive effect is obtained, followed by a multiplicity of lesser anti-personnel and light struc ture fragmentation and demolition explosions corresponding to grenade actions over a wider area than that of the immediate destructive effect of the first or parent explosion.-

Whiie I am aware of prior efiorts to obtain wider zones of dispersion as exemplified in prior multiple projectile devices, shrapnel devices and lateral barrel bomb devices, there are many objections to said prior devices which are overcome by my invention, and in addition there areno'vel and improved results attendant on use of .m'ylinvention which make it of importance in enabling attainment of objects in view in a notably simple way, and at a minimum expense, as well as avoiding disturbance of prior production practices and installations or projectile and bomb forms.

' In addition, it is sought to avoid change of procedure or materiel used in firing projectiles or dropping bombs, when my invention "is used.

An important aim of the invention is to enable the attainment of additional explosive effects involved in my invention and at the same time improve the flight characteristics and trajectory forms of bombs and projectiles of this general character.

In this specification, generally, the term projectile will be considered to include both those to be propelled by explosives'from guns or otherwise, as well as those technically called bombs to be dropped from airplanes, or planted.

t is a special aim of the invention to present a novel explosive matrix and dispersible projectiles therein wherein-novel dispersion efiects 2 :and novel initia'tion of successive detonations are attained.

Another purpose is to provide -a novel conrstructinn of grenade unit'ror inclusion innumas dispersible elements in explosive charges;

A special object is tender a novel means for protecting suc'h included uri its irom premature 'l'f-rac tui eor detonationincident' to the detonation of the m ain' bursting charge.

Another special ob'jec't' is to offer a novel firing means for-initiating thedetona'tibn of di-sperslble explosive :units following' the detonation hot the main burstingicharge "in abbnib -or projectile em- 'ibo'dying I my "invention.

It "is an "important aim of my invention to create -a more effective action in bombing from high altitudes and at night by increasing the chances of hitting important targets. "That'is to sayf oon'trary to prior practice 'offusing a *great number of very small projectiles to be scattered as bui'le'ts or shrapnel "a nd'like fragment-s, it is my aim to =-incorpo-rate in a "explosive bomb or shell a lesser number of independent explosive members which will *be each of adequate size to effect substantial demolition; which 'will be scattered by the "explosion f. the main bursting charge I of the bomb or shell [and their individual de'tonafiions initiated by the main burst. While -in lesser ii-umber than shrapnel or bullet fragme'n'ts ordinarily contemplated heretofore, the units are still in su-fficient number to'bover amply a wide area. These secondary elements may thus iun'ction' as "bombs, either high-explosive, "and/or fragmentation projectiles or as "incendiary devices gaining access to interiors of structures "the walls of which will have been opened or penetrated by'the parent carrier bomb.

'A' t'the sametime'shouid the parent fragmentation'proj ectile or bomb strike inf-a more or less 'open'area'the secondary projectiles may "extend the efiec'tive area 01f concussion and distribution to much greater distances, as "well as acting "in directions the reverse o'f those in which the primary or parent "fragments move, so that a more e-ilect'ive anti-personnelf efiect is obtained within "the efiective area ofdis'tributi-onpf fragments from the -parentdevice, v This would be particularly saleable in'a forested area against person- 'nel, or against entrenched troops "or those sheltered behind abutments orwa'lls or in craters. It 'is a special aim-of the invention alsoftoby simple expedient involving no "special struc-mral features -accomplis'h a wide variation in trajeotory individually 'or in groups, of the secondary lower or nose end portion of a bomb corresponding to one now in use;

Figure 2 is an axial section of a grenade-projectile as included in Fig. 1, actual size for one use;

Figure 3 is an enlarged detail of the fuse for the grenade;

Figures 4, and 6 are cross sections of thebomb on lines 44, 55, and 6-6; respectively of Fig. 1; i

Figure 7 is an end view of thefuse of Fig. 3 with the seal cap removed.

There is illustrated a main projectile shell body l i] which may be either one such as are fired from large caliber guns, or such as are used for 100- pound, EGO-pound or larger bombs to be dropped from airplanes.

The shellwall I l is substantially cylindrical for the major part of its length and may be either thick and grooved for fragmentation, or otherwise constructed for fragmentation, or may be thin as in demolition bombs, and the nose portion l2 may be of conventionalstructure adapted-to receive a time fuse or point-detonation fuse, or'a I conventional nose fuse [3 for bombs, as formerly illustrated here. While the nose I2 is shown integral with the wall ll, other practices maybe followed as may be current or developed for this general class of ammunition.

The particular device illustrated may be assumed to conform to and include all elements, as to structure and manner of use, of the 100-pound bomb M30 or 500-pound M43, now familiar, the tail fins being included, though not illustrated. Use of a tail fuse is optional as heretofore. My invention may be incorporated in other bombs or projectiles of different forms orstructure, with immaterial, if any, modification of practice in emdetonation upon contact with the target. The fuse may include a booster charge I5 such as tetryl or other high explosive. The internal fuse structure l3 and mechanism or its manner of installation comprise no novel detail of this invention and therefore are not illustrated.

The chamber within the shell body I0 is filled as nearly as usual with a main or bursting explosive charge I6, such as TNT tetryl or other approved explosive or mixture, preferably one which is relatively insensitive to shocks short of violent detonation, and which also is solid and resistant to compaction at ordinary temperatures to which 1 such matriel is subject during shipment and bodiment. It is contemplated that it will be found I advantageous to use my invention in the heaviest bombs, in some cases, modifying the number of secondary projectiles hereinafter referred'to so that a number smaller in proportion to'the amount of high explosive in the bomb may-be used, a relative few, say eight or ten, being sufficient for some objectives; while for others it may be desirable to include a much greater number, say one hundred or several hundred, this bomb to be dropped following other large bombs so that after a factory building, for instance, has

been collapsed a succeeding bomb will spreada myriad of small demolition charges in direct abutment with machinery in the debris where they will explode and cause further detail damage throughout the exposed material of the-factory, whereas heavy bomb explosions would act or throw fragments in paths that would pass over the exposed material or would be impeded or interrupted by masses of debris intervening between the point of detonation of the bomb and the various pieces of apparatus. The nose fuse I3 is indicated as of the Mk.- VII-MII type, having an arming vane M, which drops off in operation after a certain distance of travel of the bomb when released, to permit -head IS, the latter ternally threaded nipple or tenon for definite fragmentation storage prior to use.

In this body of the main charge, as a matrix, there is set and embedded a plurality of secondary projectiles or shells [1, all of the same size in the present instance, arranged in groups, each symmetrical and of stable equilibrium with respect to the longitudinal axis of the primary projectile. Difierent groups may, however, be of different sizes, and in any given group certain members may vary in size if symmetrically arranged with others of like size and weight or otherwise proportioned and arranged to avoid an eccentric center of gravity or unbalanced moments of force incident to flight and rotation of the primary projectile.

.These secondary projectiles each preferably corresponds to a large grenade in explosive effect, and also in fragmentation function, embodying fracturing characteristics whereby small fragments are produced for effective action against matriel or materials, when exploded immediately adjacent the target material and effective against personnel at greater distances.

The secondary projectile may be spherical or of other shape, but in the present instance, for economy of material and simplicity of production and assembly, are shown as being substantially pear-shaped, with substantially continuous smooth external surface. The projectile comprises a hollow body which may be of cast iron,

including an upper shell piece or top l8 and a lowerhead l9, joined at a plane normal to the major axis of the body a short distance from its smaller extermity. The top is substantially semispherical in its upper part, terminating in a lower slightly frusto conical wall 20 terminating at the being quartospherical and having a side wall 2| the outer surface of which is slightlyconical in alinement with and meeting thewall 20 flush, with its elements coincident with those of the wall 20.

The lower open end of the top is tapped, and the upper part of the head I9 is formed with an ex- 22 of reduced diameter, affording an upwardly presented shoulder 23 smoothly finished in a plane with the corresponding lower end surface of the top. Both the top l8 and the head 19 are suitably weakened to produce pieces of desirable sizes, and preferably, for reasons which will appear, any grooving formed for such purpose is preferably On the interior surfaces of this projectile, substantially as shown at 24 in Fig. 2. The spacing of the grooves may be varied appropriately for the purposes in view so as to produce larger or smaller fragments. The same primary or parent projectile may include secondaries grooved differently as will be appreciated. The tenonpart 22 of the head may have a number of longitudinal grooves 25 therein and the lower wall part of the top may have kerfs 26 cut interiorly or grati "'ittriorly as shown. forming the grooves intericirl'yin"the major surface areawithin the proje'ctile a-larger -quantity of explosive'may be accommodated within the projectile and also formation'of lines of cleavage is 'facilitatedand cleavage morepositively initiated by pressure of explosives fdet'cinat'ed'within the projectile, at the same time that liability of cleavage by external pressures is iniiiimised. I p

The head 19 is axially stepbored'as at '25 and *aifording a shoulder 26, the outer bore being ihteric'zrlythreaded and receiving'th'erein an exter'hally threaded fuse base 27 snugly'against'the shoulder, the base having a reduced stem 28 engaged in the inner reduced part or the bore. The

innerehd of the stem is formed with a concentric 'thin walled interiorly threaded recess 29 into which there is screwed the open exteriorly threaded end of a cylindrical fusecase 3 of thin softmetal, closed integrally at its extremity and 'havinga booster charge 3| at this closed end, to which leads "a suitable delay fuse 32. An inter- 'iiiediate igniter explosive 33 may be introduced fbetween the'fuse and booster if desired. Thefuse may be of a commercial type heretofore used for similar purposes or may be similar to grenade 'fusesfor other forms known.

The outer end of the fuse base is bored to a dis tanc'e short of the recess'29 as at 34, and a primer 'cup bore 35 is continued inwardly therefrom in which there is set a conventional percussion :pr'imer 36, a fiash partt'l' opening from the cup to the recess 29 'andhaving the fuse 32 ledtherefrom in usual manner.

The bore 34 is substantially larger than the primer cup and has fitted slidably therein a 'firing fpin31 jthepointSB of which is projected fromthe body of the pin in line with the primer. The'pin may be reduced in diameter fora "part of its length'as at 39, but is fitted full size in the outer part of 'the bore 34 and beyond the base 21 slightly. The outer face M of the fuse base when the latter is'sorewecl home li'es inwardly of a symmetrical geometrical projection of the end surface of the head 19, and. the end of the pin 31 lies approximately at this projected surface. The bore 34 'is rabb'eted at its outer end as at '40. The outer'end portion of the firing pin has a transverse hole 42' ithere'throug'h, and a soft metal wire cotter 42 is engaged through the hole and across the rabbet, resting on the end face of the base 27 to hold the pin at the outer limit of its movement, or initial and normal position.

The depth of the rabbet is less than the initial space between the point 38 and primer 36. The periphery of the base 21 is relieved as at 43 forming a circular boss on the base, its side being under cut and having the flange edges of a thin soft metal cover cap 44 crimped'th'ereinto. H The base ZIoutw'ardlyof the cup has spanner Iwriench socket-s 45 therein for screwing the base into place in assembly. g

Thespace withinthe body 6f the secondary p jectile I? is filled with a suitable explosive #6 adapted to be detonated by the booster charge 3| of the fuse. Andmay consist of TNT tetryl, or other "approved explosive suitable for one of the desired functions of the secondary projectile. In some cases the filling may be an incendiary material, in others it may be anilluininating flare on; combination of flare and incendiary material.

The cotter 42 is so formed that shoulders '41 on the pin engage outwardly of and against each side of 'tlie'bocly of the-firing pin when thecotter is inserted sothat-opposite extremities lie over the outerend-racewrtne uu'sebas'e. w

hfter'assembiytr the secondary projectile with the i-eper 'canstituterit's, trie'wnmebody and head of "the "device is encased n a "sheath or jlead so, whichiiiay he or ueh'thieliiss astocushionf the secondary projebgue ada its 'comefits from the shock ofjc'bricirssiijniiicident'todetonation oithe hiainburstiiig 'chairge iif-a boiiib inWhihi "ayb'e set, "and also to {curlreh shocks incident to toursiei; {or "the sanitary-projectile with masonry, "steel work aiiii the iik'e or by i inpact upon the secondary pidj'etue o'f 'ny-mg fragments of the ==parentshe11 orpai s rriater'i'a-l.

This lead case-5'0"inayfie irom oiiee gh'th to me' eareer'tramass-m m series, asexber'inoe may sifdtv 'tb be necessary. "other finaterials "than "'I eadaiifi ether jetja niay be us'edffor reassessment asf'bu nd available' ain'd w etie: v. In ri e-pere ri e e il b d fi 'l h 'ii 's v proj ectile in "accordance with my 1 nvention tlre e '10, sfllle f s i e we as us 1 trespassenshe v shelll" j urin g'thisfill'i'n'g in th t; operposition elative to ach other and to 'the lie rt as ne j "pea ii! shamans with trie iprposes'iiise oseqfir ein ,andare sane i intil the main charge has come serene solidified support'the secondan projeetnesinjtneir places,

I 1 1 3 .p ee' ee f th i i i i e'e. 'll heS e e pre e eb vg re e. suc l fifie w re t l 'sr i ii jb he mer .b i iiec le "in i ema low a b a l efi'i toWar'd'th'e nose ligand While it is practicable to locate a f ewoi the secondary projectiles near hqtta lg we, W thou an i h r's 'eirs w n the p:[- ,yy thb tinareriauy fdi tu t fifghtioftlwhl is are a nety'degreesjthfa n al, and a low er bombing height may be practicable,

h l r' By tn'e procedure I de m e eim 1.. a nies' ni ica e' 'ini ur s f men t e enc fit fe e i e .i jreu jrm'vfega angedjthein "in co entnc series,

nf l-1. 1 K l 39% hmwn 11 ev an a e, s of'the bomb "pproxi the secoi'l'dar rather than throwing thfilautb similar" eandproddciri'g dilly a ring di .s. elcondary action. jfAss riiiiigtiiat triiiirei toofpouniiiiddifib, the eonda actually about the size illustrated ,in ,Fig. :2. I In this weapon eight ofthe secondaryprojectiles are placed in a. concentric series .51 ,near the base of theogival curve ,52 .ofqthe nose and with their centers of gravity in} a plane normal to the longitudinal axis of the body 10. The members of this series are spacednearthe wall I l, and

clear of the-booster charge [5 and also spaced uniformly from each other. If desired this first series may be located higher in the bomb, so as to be above the boosterjS, this being a matter of discretion or to be determined by trial to secure desired effects. Some ofthe members of the group may also be located at higher levels ,in centrifugally balanced number. s

A second group 53 ofsecondary projectiles is shown spaced longitudinallyabove the first group, in which six members are shown, and these are arranged nearer the axis.v of the bomb, while a third group 5d of four secondary projectiles is shown spaced longitudinally still further above, and located closer to-the common axis of the several groups.

Owing to the greater amount of explosive that is disposed inwardly of the members of the first group than is'located within the other groups,

this first grol'll will be 1 subject to larger comd v ponents of horizontal force acting outwardly from the roof, of which the main projectile may have penetrated, so that they will in part reach beyond the immediate demolition area, or will fall among machines, structure, "etc.

During the detonation of the main charge l6 and flight of the secondary projectiles, they may be struck by flying fragments of various kinds which, withoutthe protective. sheath of lead 50 might produce destructive shocks to the shell of the small projectiles. But due to the plastic nature of lead, yet with its measure of resistance to strain these shocks are absorbed as well as the initial concussion of detonation of the main charge it itself, and the devices I! saved from I in the primary projectile.

debris and with sufficiently delayed detonationthickened wail portions of the nose of the bomb case, as well as supporting efi'ect from earth or other partly penetrated material will preserve a goodelevation of fiight'of all the projectiles l1. Differences in the angles of departure of the respective groups are generally suggested by the lines and arrows 55, 56,aricl,5'i respectively for the groups beginning with the foremost group in Fig. 1. Otherv and additional groups of secondary projectiles may be introduced, and larger numbers of the secondary projectiles, or fewer, may be included.

The uses of bombs and other projectiles carrying high explosive materials are well understood, and will not be described herein.

Upon landing and detonation of a main or parent projectile carryingjmy secondary projectiles, a, demolition effectwillbe produced corresponding to that of the conventional high explosive projectile, accompanied or not by destruction due to fragmentation of the main shell case, according to its construction. At the same time with the main explosion, the secondary projectiles will be subjected atall sides to high pressures by gases evolved within the main explosion and these gases will deform and press inwardly the lead sheath 5!! and cap 44, moving the firing pin 3! inwardly and bending. the cap metal and pin 42 into the annular recess formed by the rabbet 48 around the firingpin, until portions of the pin at each side of the firing pin are'sheared between the inner edge of the rabbet 40 and the outer edge ofthe hole Ill through the firing pin. The firing pin continues its 'movement and is driven into the primer 36 firingthe fuse train 32. At the same time, the secondary projectiles are thrown radially to various distances so that they enter breaches of wallsand the like; or are scattered within a buildingstructurethrough damage. or premature detonation.

The period of delay in the fuse of my secondary projectile must take into account the flight time value of the trajectory formed by the secondary projectile resultant onexp losion of the primary charge LS, and possibly, also, a time for rolling or richochet so that the secondary projectile may reach material at the lower part of debris. Thetotaldelaywill depend to alarge extent on the propelling effectiveness of the main charge consequent on the grouping of the secondaries Upon detonation by their respective fuses, they may act in close relation, if not immediate contact, with many pieces of equipment which may have escaped direct damage in the main explosion, adding to the destructive efiect of an attack.

, Debris will protect much material from damage by the main or succeeding demolition bombs I of conventional form, while my secondary members will be scattered through and under the will damage material from beneath where it 'might otherwise escape serious damage and be readily returned to enemy use after uncovering.

In other situations my secondary projectiles will scatter fragments from all directions from points far beyond the particular point of landing ofthe main projectile, making it difficult for personnel to obtain adequate cover.

These functions of my invention will be specially valuable against matriel, as in dispersal areas of air force concentrations and parks of motorized forces.

. In addition my invention will produce effective action even when the main projectile falls without the zone of maximum effectiveness around target as the secondary projectiles Will be thrown beyond that zone in all directions, increasing the chances of effective damage.

While I have shown and described my invention with particularity in its best construction within my knowledge, it will be understood that this is purely exemplary, and that various changes in the structure arrangement and combination of parts involved, including substitution of materials and equivalents mechanical or otherwise may be made without departing from the spirit of the invention as set forth in the appended claims.

I claim:

1. In an explosive projectile, a main bursting charge, a plurality of secondary projectiles completely embedded in said main charge as asupporting matrix, each secondary projectile comprising a hollow body of fragmentizable mate rial and containing an explosive charge, a delay action'fuse extending into said explosive charge, including a primer and firing pin, said pin having a portion extending to a, point adjacent the periphery of 'saidbody, and a shell of yielding cushioning material completely inclosing said body and having a portion adjacent the firing pin constructed and arranged to yield in response to the force of the explosion of the main bursting charge to operate said pin to cause the explosion of the secondary projectile.

2. In an explosive projectile, a main bursting charge, a plurality of secondary explosive projectiles completely embedded in said main charge as a supporting matrix, each secondary projectile being provided with a delay action fuse including a primer and a firing pin, said firing pin extending to a point adjacent to the periphery of the body of said secondary projectile, and a continuous unbroken shell completely inclosing said projectile, said shell yielding in response to detonation of said main charge to contact and actuate the firing pin to explode the secondary projectile.

3. In an explosive projectile, a main bursting charge, a plurality of secondary explosive projectiles completely embedded in said main charge as a supporting matrix, each secondary projectile comprising a hollow body, an explosive charge in said body, a delay action fuse in said body extending into said charge, said fuse being provided with a base extending to a point adjacent the periphery of said body, said fuse including a primer and a sliding firing pin, a plate of flexible material engaging the firing pin, and a shell completely surrounding said body and said plate, and having a flexible portion adjacent the firing pin and responsive to the force of the explosion of said bursting charge whereby said firing pin is actuated to ignite the charge in the secondary projectile upon the explosion of said main charge.

4. An explosive projectile comprising a main shell body containing a main explosive charge, and a plurality of secondary explosive projectiles completely embedded in and supported by said main charge, each said secondary projectile comprising, a hollow secondary body having an explosive' charge therein, a fuse positioned within the charge in said secondary body and secured within an opening in the wall of said secondary body, and a continuous unbroken sheath of cushioning material surrounding and enclosing said secondary body and fuse, said fuse including a firing pin operated by deformation of said sheath in response to detonation of said main explosive charge.

5. In an explosive projectile, a shell body having a central longitudinal axis and containing a main explosive charge, and a plurality of secondary explosive projectiles completely embedded in and supported solely by, said main explosive charge, said secondary projectiles being arranged in a plurality of series, said series lying in respective planes normal to and spaced along said axis, the projectiles of each series being symmetrical about said axis, the projectiles in each series decreasing in number from the nose of said shell body, the radial distance from said axis of the projectiles of the respective series, decreasing from the nose of said shell, whereby 0n detonation of said main explosive charge, said secondary projectiles are dispersed substantially uniformly over an area.

GARLAND L. HARRELL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 174,325 Tyler Feb. 29, 1876 1,284,148 Saladiner Nov. 5, 1918 1,791,716 Davis et al. Feb. 10, 1931 2,361,955 Moore et al Nov. 7, 1944 FOREIGN PATENTS 40 Number Country Date 22,786 Great Britain 1914 

